(MAMMOTH CAVE NATIONAL PARK -- November 3, 2006) Mammoth Cave National Park scientists and public health officials are working to find the source of elevated levels of fecal coliform and E. coli bacteria found in the groundwater inside one section of Mammoth Cave earlier this week. Tours have been closed in the Historic section of the cave as a precautionary measure to keep visitors out of areas where possibly contaminated water may drip on them.

"This is not something we expected," said Superintendent Patrick Reed. "A researcher discovered the organisms while looking for something else. Now that we know of the problem, we are exploring every possible source. We’re proceeding in a deliberate manner, pulling in experts from Western Kentucky University (WKU), Caveland Environmental Authority (CEA), and the U.S. Public Health Service. Our primary concern is to protect the public, employees, and the cave."

Rick Fowler of WKU’s WATERS Lab collected groundwater samples at a cave waterfall (Charon’s Cascade, below River Hall) on October 20 for water chemistry testing. Upon returning to the lab, he ran a full-spectrum analysis for bacteria as well; the October 26 results of the lab work revealed levels of fecal coliform and E.coli bacteria in excess of recreational water/bathing public health standards.

Fowler immediately reported his findings to the park. Park staff retested Charon’s Cascade and additional locations along the Historic tour route; results received on October 30 showed levels at Charon’s Cascade had fallen, but all of the locations measured had levels that exceeded public health standards. At that time, as a precautionary measure, tours into the Historic section of the cave were cancelled.

Test results received on October 31 showed a return to safe levels at all locations, but Reed decided to keep the Historic section of the cave closed until he is confident the area can be toured safely.

"We want to be cautious," Reed said. "We apologize for any inconvenience to our visitors, but our first responsibility is their health and safety and that of our employees."

E.coli is a group of bacteria that contains hundreds of different strains. Most strains are harmless, but some produce a toxin that may cause illness. E.coli has been found in the intestines of farm and forest animals, and humans. Park scientists have not yet determined whether the E.coli discovered are the harmful strain.

"Our main safety concern is to prevent visitors from swallowing or getting contaminated water on their hands, eyes, nose or mouth," said Theresa McDarmont, U.S. Public Health Officer, who is currently in the park. "We are stressing hand-washing as the best way to prevent illness." While there is no evidence that anyone has become ill from visiting or working at the park, McDarmont recommends that any person who is exhibiting symptoms, such as diarrhea or nausea, should see his or her physician.

"It appears the problem was confined to the Historic section of the cave," said Mike Adams, chief of interpretation at Mammoth Cave. "We have temporarily transferred all our tours to the Frozen Niagara section of the cave, which is three miles away from the Historic Entrance, in a different drainage basin that has tested well within safe levels. We will continue to monitor the groundwater where we are conducting tours to ensure public safety."

"Right now we still have a lot of unknowns," added Superintendent Reed. "CEA monitoring devices show no change in sewage flow. Initial tests of the water flowing out of parking lot runoff filters show they might be a source. Our goal is to find the source and stop the contamination. In the next days and weeks, our staff will monitor groundwater on a continuing basis. We will also begin tests to determine what strain of E.coli we are dealing with and whether it comes from a wildlife or a human source."